Statement of the Technical Field
The technical field of this disclosure comprises radio frequency signal source identification, and more particularly concerns methods and systems for passive identification of an entity responsible for certain transmissions.
Description of the Related Art
The related art concerns communication networks which are defined in accordance with a Long-Term Evolution (LTE) standard for high-speed wireless communications for mobile phones and data terminals. In an LTE network one or more User Equipment (UE) devices communicate using an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN). In an LTE system, the E-UTRAN is comprised of a plurality of evolved base transceiver stations called eNodeB or eNB. Each eNB is usually a fixed station, and is used to control the EU devices in one or more cells. Each eNB comprising the E-UTRAN communicates with an Evolved Packet Core (EPC). The EPC utilizes packet data to communicate with packet data networks outside of the LTE architecture, including the internet and/or private corporate networks.
Each eNB in an LTE network sends and receives radio frequency transmissions to the UE's within its cell in accordance with a defined LTE air interface. To facilitate such communications, each eNB is comprised of radio frequency (RF) transmitter and receiver. An RF transmission from the eNB to an EU is generally referred to as a downlink communication. In contrast, a communication from the UE to the eNB is referred to as an uplink communication. In addition to facilitating communication of traffic data, the eNB also controls various operations of EU's within its cell by communicating signaling and control messages.
In accordance with an LTE air interface, UE communications with an eNB are time and frequency multiplexed. The uplink air interface can be defined by a physical uplink shared channel (PUSCH). Access to the PUSCH is time and frequency synchronized among a plurality of UE's to minimize interference. Additional details concerning the physical channels for evolved UMTS Terrestrial Radio Access (E-UTRA) are set forth in the ETSI TS 136 211 Technical Specification (version 9.10.0 or later), produced by the European Telecommunication Standards Institute (ETSI) 3rd Generation Partnership Project (3GPP).